Abstract

The performance of high-gain, fast-ignition fusion targets is investigated using one-dimensional hydrodynamic simulations of implosion and two-dimensional (2D) hybrid fluid-particle simulations of hot-electron transport, ignition, and burn. The 2D/3D hybrid-particle-in-cell code LSP [D. R. Welch et al., Nucl. Instrum. Methods Phys. Res. A464, 134 (2001)] and the 2D fluid code DRACO [P. B. Radha et al., Phys. Plasmas12, 056307 (2005)] are integrated to simulate the hot-electron transport and heating for direct-drive fast-ignition targets. LSP simulates the transport of hot electrons from the place where they are generated to the dense fuel core where their energy is absorbed. DRACO includes the physics required to simulate compression, ignition, and burn of fast-ignition targets. The self-generated resistivemagnetic field is found to collimate the hot-electron beam, increase the coupling efficiency of hot electrons with the target, and reduce the minimum energy required for ignition. Resistivefilamentation of the hot-electron beam is also observed. The minimum energy required for ignition is found for hot electrons with realistic angular spread and Maxwellian energy-distribution function.

Received 14 August 2008Accepted 18 September 2008Published online 07 November 2008

Acknowledgments:

This work was supported by the U.S. Department of Energy under Cooperative Agreement Nos. DE-FC02-04ER54789 (Fusion Science Center, Office of Fusion Energy Science) and DE-FC52-08NA28302 (Office of Inertial Confinement Fusion), the University of Rochester, and the New York State Energy Research and Development Authority. The support of the DOE does not constitute an endorsement by the DOE of the views expressed in this article.